Improvement in air-brakes



w. n.1uNEs.-

Air-Brakes.

MFETES, PHOTO-UTNOGHAFMEF. SHINGTON n C P-atehted Aug. 3, 1875.

UNITED STATES PATENT OFFICE W. DAVIDSON JONES, OF HAGAMANS MILLS, NEW YORK.

IMPRovEwnIixiT- IN AIR-BRAKES.

Specification forming part of Letters Patent No. 166,386, dated August 3, 1875; application led July 27, 1875.

To all whom it may concern Be it known that I,.W. DAvIDsoN JONES, of Hagamans Mills, in the county of Montgomery and State of New York, have invented a new and useful improvement in automatic supply relief valves for operating compressed air brake cylinders; and I do hereby declare the following` to be a full, clear, and exact description thereof, reference being had to the accompanying drawings, making part of this specification, in which- Figure l is a side elevation of the valve.

' Figs. 2 and 6 are sectional views of Fig. l, on

the plane of the line fr x in Fig. 5, showing the induction and eduction ports, the com-l pound trunk-valve B B, and valve c on the stem c', held to its seat m m by springs 3 3. Fig. 3 is a transverse section of the end of Vtrunk-valve B B, showing the passage@l and valve-stem guide n. Fig. 4 is a transverse sectional viewof the opposite end of the compound trunk-valve B B, showing the valve c and valve-stem guide a. Fig. 5 is an elevation of the valve, looking at the ports h and k.

Like letters and lignres of reference indicate like parts in each drawing or ligure.

My invention relates to that class of compressed air-actuated car-brakes in which the air is conveyed back to reservoirs beneath each car by a pipe from a main reservoir on the engine, the compressed air from the auxiliary reservoirs on each car of the train operating a movable piston within a cylinder, thereby applying the brake-blocks to the'wheels, as is commonly done. By the interposing of my invention in close connection therewith, and between or by its use forming the connections between the auxiliary reservoir, the vcylinder containing the piston, and the branch-pipe from the main supply-pipe, the brakes may be rapidly and readily applied, and as' rapidly and readily released, at the will of the engineer, or automatically set on all the cars of the train, should the cars become uncoupled, or the main supply or branch pipes become broken, as will be hereinafter fully set forth.

My improved automatic-supply relief-valve for connecting the branch induction-pipe with the auxiliary reservoir, and at the same ti e closing connections with the brake-cylinder,

and at the will of the engineer (or in case of accident uncoupling of cars, or rupture of main pipe from the reservoir on the engine or tender) to close such connections, and to `automatically open connect-ions between the auxiliary reservoir and the brake-cylinder, thereby allowing the compressed air to pass to said cylinder, actuating the piston ,thereof and applying the brakes, as is usually done, and as readily' relieving the cylinder ofthe compressed air, and discharging it by opening communication from the cylinder with the atmosphere, and at the same time restoring the connection between the main supply-pipe and auxiliary reservoir by decreasing and increasing the pressure in the main supply-pipe running the whole length of the train.

My invention may be used to operate the pistons of brake-cy linders attached to each car where there is no auxiliary reservoir employed, and discharge the compressed air directly from the cylinder, after doing its work, into the atmosphere, without returning it to the engine through the supply-pipe, the same being done by simply cutting off the .supply or pressure from the main supply-pipe.

To enable others skilled in the art to make and use my invention, I will proceed to describe its construction and operation.

A is a valve-case, made substantially as shown, and provided with a cap, A', containing the induction pori or passage y, saidport connecting with the main supply-pipe from the engine, and being also provided with eduction pipe or port g, to which is connected the auxiliary reservoir and eduction induction port k communicating with the brake-cylinder, and eduction-port h communicating with the atmosphere. rEhe cap A is secured to the shell-case A by bolts 2.

The compound trunk-valve B, Figs. 2 and 6, is made of proper form, ,substantially as shown, having the circumferential depression o, Figs. 2 and 6, and valve-seat m, valve c on valve-stem c', is held in vposition by valvestem guides n n, Figs. 3 and 4. Said valve c is held to its seat m, Figs. 2 and 6, by spiral spring 3.

' The operation of my invention is as follows: With the port y, Figs. 1, 2, 5, and 6, connection is made with the supply-pipe leading from the main reservoir on the engine. With the port g connection is made with the auxiliary reservoir. Vith the port k connection is made win the brake-cylinder, operating a piston within, and port h communicating with the atmosphere.

Compressed air being admitted from the main reservoir attached to the engine, through a three-way cock, into the supply-pipe and its branches to each car of a train, the compound trunk-valve B would be driven by the compressed air to the rear or lower end of the case A, and closing port la leading to the brake-cylinder, as shown in Fig. 2, the strength of the spiral spring 3 holding valve c to its seat m suiiiciently firm to carry the compound trunkvalve B to the lower end, as shown in Fig. 2; the pressure would then unseat valve c on stem c and allow the air to pass, through port y, passage a, and port g, into the auxiliary reservoir. The pressure in the auxiliary reservoir would be about equal to the pressure in the main reservoir and supply-pipes. The brakecylinder would communicate with the atmosphere through port-k, circumferential depression o, and eduction-port IL, thereby leaving the piston free to return tothe back ofthe cylinder by the action of the throw of springs attached to the brake-blocks, or through any other suitable agency. A Then the engineer wishes to put on the brakes he turns the three-way cock near to him in the supply-pipe, cutting off' communication with the main reservoir and opening communication with the atmosphere in that portion of the supply-pipe in rear or back of the three-waycock, thereby reducing the pressure in that portion of the supply-pipe and its .branches leading to each automatic-supply relief-valve, which, by the excess of pressure retained in the auxiliary reservoir, would force a current of compressed air backward,closing tirmly on its seat the valve c, Figs. 2 and 6,

and driving the conpound trunk-valve B into the forward part of valve-case A, as indicated by the dotted or broken lines in Fig. 2, and

fully shown in Fig. 6, therebyr opening full and free communication from the auxiliary reserlvoir, through ports g and lc, into the brakecylinder, thereby moving the piston, and, by

suitable connections from said piston to the brake-blocks, applying the brakes.

When the train is stopped and the engineer wishes to take oft' or release the brakes, he turns the three-way cock so as to close communication with the atmosphere and open communication from the main reservoir on the engine with the supply-pipe, and to each automatic-supply relief-valve, which, by the excess of pressure in the main reservoir and supply-pipe over the reduced pressure of the expanded air in the auxiliary reservoir and brakecylinder, causes a current of air to pass into the port y, Figs. 2 and 6, and, by the spring V3, holding Valve c on its seat m, the compound trunk-valve B, Figs. 2 and 6, is driven from the position just described and fully shown in Fig. 6 to the position shown in Fig. 2, atthe bottom or back end of the valve-case A, and simultaneously closing port k from communication with port g, Fig. 2, from the supply-pipe unseating Valve c and passing into the auxiliary reservoir until the equilibrium is restored, and, with thereturn of the compound trunk-valve B to the position shown in Fig. 2, communication is opened from the brake-cylinder, through port 7c, circumferential depression 0 on the compound trunkvalve B, and port 7L, Fig. 2, with the atmosphere, thereby allowing the air in the brakecylinder to instantly escape, releasing at once,

through the medium of the piston and connections, the brake-blocks.

It is, evident that my invention can be used as a simple relief-valve, without any auxiliary reservoirs, by placing it between the brakecylinder under each car and the branch-pipe leading from the supply-pipe, and making the following connections, that is, connecting the branch-pipe to the induction-port y, Figs. 2 and 6, and the brakecylinder to port g, plugging port 71 as shown in Fig. 5, by cross shading, to prevent dust and like matter from entering, as that port is not used.

The operation as a simple relief-valve is as follows: When the engineer wishes to put on brakes he turns the three-way cock in the supply-pipe, thereby closing communication with the atmosphere and opening communication from the reservoir to each car through the supply-pipe and branch to port y, Figs. 2 and 6, forcing the trunk-valve B to the back end of the case A, thereby closing eduction-port k, as shown in Fig. 2, when the compressed air will unseat valve c and pass from the branch-pipe through port y, air-passages a, and port g, into the brake-cylinder, actuating the piston and putting on the brakes.

To release the brakes the engineer turns the three-way cock so as to close communication with the reservoir and open communication with the supply-pipe running back through the train with the atmosphere. As soon as the pressure in the supply-pipe is reduced the back flow from the brake-cylinder commences, driving the compound trunk-Valve B into the forward part of case A, as shown in Fig. 6, and opening communication from the brake-cylinder, through ports g and k, into the open air, thereby releasing the brake-cylinder piston and, through its connection, the brake-blocks.

The compound trunk-valveB may be packed at each end to prevent the leaking and injury, if so desired, and the valve-seat m may also be packed with suitable packing.

This supply relief-valve is automatic in its operation, is durable, and is free from liability to get out of order.

A stop-cock may be placed in the pipes leading from the auxiliary reservoirs to the valveports g on each car, so as to close the same in the compressed air What I claim, and desire to secure by Letters Patent, is-

The combination, with the valve-casing having ports y, g, 71 and k, of the hollow pistonvalve and check-valve inolosed therein, to open with the pressure, the ends of the pistonvalve having perforated cross-bars to support the stein of the check-valve, substantially as and for the purposes specified.

W. DAVIDSON JONES.

Witnesses:

WM. M, PAWLINGS, HENRY E. GREENE. 

